This invention relates to magnetic disk storage devices, and more particularly it is concerned with a magnetic disk storage device capable of avoiding generation of vibration and production of dust in magnetic disks and magnetic heads and off-track of the magnetic heads with respect to the magnetic disks.
In order to increase capacity and improve system throughput, a magnetic disk storage device has in recent years been developed which comprises a multiplicity of magnetic disks stacked in superposed relation, and two actuators arranged symmetrically with respect to a spindle supporting the magnetic disks and having access to the magnetic disks. This type of magnetic disk storage device is described in U.S. Pat. No. 4,190,870, for example.
In this type of magnetic disk storage device, the magnetic disks rotate at high speed or at a speed of rotation in the range between 3000 and 3600 rpm. Thus, currents of air which are large in volume would flow at high speed in a head disk assembly and cause the magnetic disks and magnetic heads to vibrate, thereby adversely affecting operations of recording and reproducing data on and from the magnetic disks by means of the magnetic heads.
Owing to the high speed at which the magnetic disks rotate, windage loss might generate heat in the magnetic disk storage device. The heat thus generated would cause expansions of the magnetic disks each including a base formed of aluminum and tilting of the spindle supporting the magnetic disks, with a result that an error would be made in positioning the magnetic head on a desired track of one of the magnetic disks of the device.